Among all the other changes that iOS 11 brought to HomeKit, it completely reworked the way Bluetooth accessories communicated. Elgato updated the firmware on a trio of their popular HomeKit accessories to take advantage of these new changes and they now operate nearly instantly.

In iOS 10, there was quite the process that kicked off whenever a state change happened to a Bluetooth accessory.

When there was a state change (such as a contact sensor on a door opening), it would send a notification to your Home Hub. The Home Hub would then communicate back to the accessory to determine what state was changed. Last, it would trigger the automation (such as turning on the lights).

All of that communication would result in a few seconds of latency. When you arrive home, and open your door, you want the lights to come on instantly, and not wait for your motion or contact sensor.

iOS 11 completely changed how the process works. Instead of that back and forth, the Bluetooth accessory encrypts the state-change into a secure-broadcast notification to your Home Hub. That notification includes the change, removing the need for the back and forth. Once your Home Hub received the secure-broadcast notification, it then triggers the scene or accessory.

Now, whether it is a contact sensor, motion sensor, or any other Bluetooth accessory, it reacts immediately with no delay.

To take advantage of these changes, manufacturers need to issue an update to their devices, and Elgato has now done that to the Eve lineup. The Eve Motion, Eve Door & Window, and Eve Wall Switch recently got OTA firmware updates to support this latest change.

In the past, we’ve reviewed each of these three accessories and while they performed well overall, the biggest negative was the delay from HomeKit.

After the update, I immediately saw an improvement in performance. After living with this 2-3 second delay for quite a while, the instantaneousness really makes a different.